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Measuring & Mapping

Where, how far, and how much? People have invented an astonishing array of devices to answer seemingly simple questions like these. Measuring and mapping objects in the Museum's collections include the instruments of the famous—Thomas Jefferson's thermometer and a pocket compass used by Meriwether Lewis and William Clark on their expedition across the American West. A timing device was part of the pioneering motion studies of Eadweard Muybridge in the late 1800s. Time measurement is represented in clocks from simple sundials to precise chronometers for mapping, surveying, and finding longitude. Everyday objects tell part of the story, too, from tape measures and electrical meters to more than 300 scales to measure food and drink. Maps of many kinds fill out the collections, from railroad surveys to star charts.

This small clock from the early 1850s is unsigned, but its movement is likely from a Connecticut clock factory and its case is likely a product of the Litchfield Manufacturing Co., Litchfield, Conn. The Litchfield firm was America’s first paper-mâché factory, founded by English immigrants in 1851 and eventually employing about 50 men and women. The firm used a patented British process for mother-of-pearl inlay to decorate an array of goods in addition to clock cases, including tables, card cases, fire screens, boxes, vases and ornamental hinges and clasps. The Litchfield firm failed after a merger in the mid-1850s that bankrupted its major supporter, showman P.T. Barnum.

This clock’s base is made of wood, the body is made of black papier-mâché, with mother-of-pearl inlay and painted images on front and gilt edge paint. The white enamel dial features Roman numerals. The brass movement has steel mainsprings, and the entire clock is covered with glass dome.

Joseph Hall of London, England, made this clock about 1680. It is a weight-driven style of domestic clock made entirely of metal and named after its shape, which roughly resembles a lantern. English emigrants from Bermuda purportedly brought the clock to Massachusetts around 1700.

At that time, a brass lantern clock or a tall case clock with a brass movement would have been among the most expensive items its owners possessed. More important as status symbols than as precise timekeepers, the clocks often had only an hour hand. Most people did not require to-the-minute accuracy.

Made about 1825, this clock represents an effort to incorporate imported springs, instead of falling weights, to drive the movement. At the time of its manufacture, there was no spring-making industry in the United States. The brass time-and-strike movement runs for eight days. The white-painted metal dial has Roman numerals, with separate seconds under numeral 12, and decorative shell spandrels. The mahogany case has front paw feet and a two-part front door. The door is inlaid with two brass strips; the ivory keyhole escutcheon is missing. The door’s upper glass covers the dial and the lower glass has a reverse-painted scene featuring two structures within a gilded border. There is also a gilded border encircling a clear opening to view the pendulum. The pendulum bob is brass-covered lead.

Inside the case is a printed label that reads: “Eight Day Brass Clocks Made by Curtiss & Clark, Plymouth, Con. This Clock combines advantages over any other Clock made in this country, for convenience. It is made of the best materials, the springs imported from Geneva. All the directions necessary for this Clock are, when the Clock is oved, take off the pendulum ball, and tie down the rod; when set up, set it in a perpendicular position, in order to its having an equal beat. Printed by P.B. Goodsell, printer. Hartford."

Heman Clark, once an apprentice to Connecticut clockmaker Eli Terry, designed this type of clock. Clark’s brother Virtue Clark manufactured about a hundred of these clocks with Garner Curtis(s) for about a year beginning in 1824.

Eli Terry manufactured this clock in 1817 or 1818. Inside its plain box case, the clock features a label with an equation-of-time table for setting clocks with a sundial.

The equation of time refers to the relationship between clock time and sun time. As the relationship of Earth to the sun changes with the seasons, the sun appears to run faster or slower than the clock. The differences between the unvarying clock and the sun accumulate as the year progresses and are charted, like on this clock, as the equation of time.

Terry was one of a handful of a handful of Connecticut inventors and entrepreneurs who transformed the way clocks were made in the United States in the opening years of the 19th century. Recognizing a vast potential market for low-cost domestic clocks, Terry and his associates Seth Thomas and Silas Hoadley applied water-powered machinery to clockmaking. One of the proving grounds of the American Industrial Revolution, clockmaking changed from a craft to a factory process in which machines mass-produced uniform, interchangeable clock parts. This manufacturing technique appeared in other industries about this time and became known as "the American system" of manufacturing.

The process called for a whole new kind of clock. The first mass-produced clocks had movements of wood, instead of scarce and expensive brass. Although the earliest of these wooden clocks had long pendulums and fitted into traditional tall cases, about 1816 Terry designed a distinctly American clock small enough to set on a mantel or shelf. Sold largely to rural buyers by itinerant merchants, these clocks played an early and significant role in transforming the rural North from overwhelmingly agricultural to a modern market society.

This wall clock, made about 1880 by A. Hahl & Company in Baltimore, was one of several hanging in classrooms at Jefferson Junior High School in Washington, D.C. A mechanical master clock, located elsewhere in the building, pumped a pulse of air once a minute through tubes to this clock and others connected in a system. The pulse advanced multiple clocks’ hands simultaneously and synchronized them automatically, features that grew in popularity as the size of buildings increased in the nineteenth century. Pneumatic systems competed with early electric clock systems, which were often unreliable.

The air clock technology is based on patents (No. 140661, granted 8 July 1873, and No. 196404, granted 23 October 1877) by Hermann. J. Wenzel, a German immigrant who settled in San Francisco. Wenzel went into business with Augustus Hahl, another German immigrant, who had an establishment in Baltimore, Md., for making and selling bells systems, burglar alarms and other electrical apparatus. A. Hahl & Company sold this pneumatic clock system to the D.C. schools.

Clocks were important in school rooms. As early as the 1830s in the United States, white children were attending free public elementary schools where they were conditioned to the clock-regulated day. A ringing bell called them to class. A clock in each classroom organized their lessons, and among the first things they learned was how to read the clock dial. Strictly enforced schedules were intended to instill time discipline, preserve social order and underline moral values. Students were punished for tardiness and awarded certificates for punctuality.

This is an example of an Ithaca Calendar Clock model called “3 ½ Parlor” from the mid 1870s. Its walnut case has ebonized decorative elements. The black upper dial shows the time in white Roman numerals, with winding arbors at IIII and VIII for the brass eight-day time-and-strike spring-driven movement behind the dial. Lower clear glass has reverse-painted white Arabic numerals for date of the month. Metal calendar apparatus visible inside case, where rotating wheels show weekday and month.

The Ithaca Calendar Clock Co., established in Ithaca, N.Y., about 1865, made clocks based on the automatic perpetual calendar mechanism patented by Henry Bishop Horton in 1865 and 1866 (see patent 57,510).

This clock dates from the 1930s, when the popularity of electric clocks began to surpass mechanical ones. In the late 1870s, mass produced spring-driven alarm clocks had first become available for as little as $1.50. The alarm clock became a fixture in bedrooms across the country. In the 1920s, inexpensive electric versions, plugged into house current, appeared. By 1933, roughly sixty percent of all clocks made and sold annually—with and without alarms—were electric.

The internal workings of this clock were made in Ashland, Mass., by the Warren Telechron Co. for General Electric Company. The dial is marked “General Electric” and “Telechron.” The small circular opening under the 12 on the dial is a power indicator. If the power to the clock failed, a red dot appeared in the opening. Resetting would cause the red dot to disappear. Reflecting the art deco influences of that decade, the clock features an alloy case with a black plastic base. Evolved from a firm making window mechanisms for automobiles, the Dura Company of Toledo, Ohio, manufactured the case, an art deco style based on design patent D85,094 granted to George Louis Graff of the same city in 1931.

The modern electric alarm clock has its origins at the Warren Clock Company, Ashland, Mass., in 1912 when Henry Warren made battery-driven electric clocks and experimented with a small clock that operated with power from the electric mains. In 1918 Warren received a patent for a self-starting synchronous motor small enough to power a clock. His clock required a steady flow of 60 cycles per second of alternating current. He discovered that his clocks failed to keep time because the frequency of current from the local power company, Boston Electric, fluctuated. Warren’s next invention, a master clock for power stations, remedied the situation.

In 1917 General Electric purchased a 49% interest in the Warren Clock Company (renamed Warren Telechron Co. in 1926) and used Telechron motors in its clocks. At first clocks appeared only under the Telechron name, but after about 1930, a line of products made in Ashland bearing the General Electric name began to appear. In 1943, when Henry Warren retired, General Electric acquired a controlling interest in the firm and continued making electric clocks until 1979.

From its infancy, timekeeping has depended on astronomy. The motion of celestial bodies relative to the rotating Earth provided the most precise measure of time until the mid-twentieth century, when quartz and atomic clocks proved more constant. Until that time, mechanical observatory clocks were set and continuously corrected to agree with astronomical observations.

The application of electricity to observatory timepieces in the late 1840s revolutionized the way American astronomers noted the exact movement of celestial events. U.S. Coast Survey teams devised a method to telegraph clock beats, both within an observatory and over long distances, and to record both the beats and the moment of observation simultaneously. British astronomers dubbed it the "American method of astronomical observation" and promptly adopted it themselves.

Transmitting clock beats by telegraph not only provided astronomers with a means of recording the exact moment of astronomical observations but also gave surveyors a means of determining longitude. Because the Earth rotates on its axis every twenty-four hours, longitude and time are equivalent (fifteen degrees of longitude equals one hour).

In 1849 William Cranch Bond, then director of the Harvard College Observatory, devised an important improvement for clocks employed in the "American method." He constructed several versions of break-circuit devices—electrical contracts and insulators attached to the mechanical clock movement—for telegraphing clock beats once a second. The Bond regulator shown here incorporates such a device. Bond's son Richard designed the accompanying drum chronograph, an instrument that touched a pen to a paper-wrapped cylinder to record both the beats of the clock and the instant of a celestial event, signaled when an observer pressed a telegraph key.

Johannes Van Ceulen made this clock in The Hague, Holland, in collaboration with Christiaan Huygens. Huygens (1629-1693) patented the design for the first practical pendulum clock in 1657.

In common with other so-called “Hague clocks,” which were made in several Dutch cities and by other clockmakers in Huygens’ time, this Van Ceulen clock has a single spring that drives both time and strike trains, a pendulum suspended between curved “cycloidal cheeks” (designed to correct the oscillation period of the pendulum for variations in its swing’s amplitude) and an ebonized fruitwood case reminiscent of classical architecture. The pediment of the case, with its gilt floral pattern, serves not only a decorative function, but also conceals the clock’s externally mounted bell. Also typical are the velvet-covered brass dial plate and the prominent figure of Chronos, or Father Time. The figure supports the chapter ring and rests on two signature plaques inscribed “Johannes Van/Ceulen Haghe.” The backplate is also marked “Johannes Van Ceulen/Fecit Haghe.” This clock has a two-day movement, verge and crown wheel escapement with crutch, silk thread suspension for the pendulum and count wheel striking. The alarm work is missing.

References:

1. Mahoney, Michael S. “Christian Huygens: The Measurement of Time and of Longitude at Sea,” in Studies on Christiaan Huygens, Edited by H.J.M. Bos et al. (Lisse: Swets, 1980), 234-270.

After decades of experiments with the pendulum, Galileo Galilei (1564-1642) conceived of a pendulum clock that could be used to determine longitude at sea. Near the end of his life, blind and in failing health, he discussed the design with his son Vincenzio and his biographer Vincenzo Viviani. His son made a partial model and his biographer made or commissioned a drawing of the incomplete model after Galileo’s death.

The model in the Museum’s collection, made by New Jersey instrument maker Laurits Christian Eichner in 1958, is based on the seventeenth-century drawing preserved in the Biblioteca Nazionale Centrale, Florence, Italy. It is made of iron and features a pinwheel escapement and a pendulum.

During the seventeenth century, the problem of finding longitude at sea was among the leading topics in scientific research. The idea of using a precise clock to find longitude dated from the century before, but no such clock existed. Clocks in Galileo’s era told time only to the nearest quarter hour and allowed only crude rate regulation. The pendulum-regulated clock, first conceived by Galileo and then realized by Christian Huygens of the Netherlands in 1656, proved unsuitable for finding longitude on a rocking ship, and a good solution to the longitude problem would not appear until the marine chronometer at the end of the 18th century. But the pendulum clock revolutionized precise time for astronomy and other research by measuring time accurately to the second.